Stop-knob



(No Model.)

M. CLARK.

STOP KNOB. No. 394,246. Patented Dec. 11, 1888.

7158165666.- izz/e212??? JZMWM M J/Zi br/ZZZ v UNITED STATES PATENTOEEIcE.

MELVILLE CLARK, OF CHICAGO, ILLINOIS.

STOP-KNOB.

SPECIFICATION forming part of Letters Patent No. 394,246, dated December11, 1888.

Application filed April 27, 1888. fierial No. 272,028. (No model.)

To all whom it may concern.-

Be it known that I, MELVILLE CLARK, a citizen of the United States,residing at Chicago, county of Cook, and State of Illinois, haveinvented certain new and useful Improvements in Stop-Knobs, which arefully set forth in the following specification, reference being had tothe accompanying drawings, formin a part thereof.

In the drawings, Figure 1 is an axial section through a knob and itsshank. Fig. 2 is a side elevation of the knob detached from the shank.Fig. 3 is an axial section of the shank with the knob detachedtherefrom. Fig. 4 is a side elevation of a knob of slightly-modifiedconstruction. Fig. 5 is a similar elevation with a further slightmodification.

The purpose of this invention is to provide a knob of such form as maybe made of porcelain, or of glass or like substances which cannot bereadily worked after they are made, and whose surfaces or substances areof such character that glue or other adhesive cements will not adhere tothem, and which, therefore, cannot be joined to their shanks by thatmeans.

It consists in forming the knob with the usual head or body, A, havingthe stop-shoulder a, and, in addition, having protruding from the baseend, and preferably from the center thereof, a tenon, A. This tenon maybe of any shape, but is most conveniently made round, and is mostconvenient-1y attached when it is in this shape. The peculiar feature ofit, however, consists in depressions a, formed in its surface. Thesedepressions may be independent circumferential grooves, as shown in Fig.2; or they may be a continuous spiral groove forming a screw-thread, asin Fig. 3; or they may be indentations of any form, and regularly orirregularly distributed over the surface, as shown in Fig. 4. Thesedepressions serve the purpose of receiving any plastic ma terial whichhas a capacity for afterward hardeningas glue or plaster-of-paris orother eenientwhich is cemented in the socket B formed in the end of theshank B, before the knob is applied to the shank, by inserting its tenonA in said socket B. The size of the socket B should be substantiallythat of the tenon A, so that the tenon will fit snugly in the socket,but not so closely but that it may be thus inserted when it has beensmeared with the cementing material sufficiently to fill the depressionsa and leave a film on the surface. Having been thus inserted, thecenient, hardening, will adhere to the wood if it is of adhesivesubstance, as glue; and whether adhesive or not will form projectingrings or points or screw-thread, 2tC('()I'(llll L {i() the form of thedepressions in the tenon. engaged in said depressions, and so preventthe tenon from being withdrawn and the knob being detached from theshank. I deem it preferable in some cases to form similar depressions,b, in the inner surface of the annulus of wood remaining about thesocket B in the shank, into which similar projections of the cementingmaterial will protrude and operate as a key engaging both partsthat is,the knob and the shankto prevent their separation. This construction isespecially desirable, in that it permits the use of such material asporcelain or glass, which can be highly ornamented, and which cannot besecured to the shank by the ordinary methods which are suitable forwooden and metal knobs, the only method heretofore available beingeither to put a screw through from the face of the knob, which rendersit unsuitable for a stopknob, or to secure a screw into the base bysoldering the same; and this is objectionable, first, because thejunction between the screw and the knob is not secure, and, second,because when the knob is tightened on the shank the name on the facewill not always come into correct position, and in attempting to forceit farther around, in order to bring the name right, either the knobbecomes detached from the screw or the screw loses its hold in the wood,which it must enter lengthwise of the fiber; but by the constructionwhich I have hereinabove described knobs of such material as porcelainand glass can be secured, so that when the cement is hardened they areunremovable, and are even more secure than a wooden knob would be ifglued to the shank in the more usual manner.

As a precautionary measure, I form in the tenon A a transverse hole, athrough which a pin, C, maybe inserted if it should ever become loosenedin the shank. This hole being always made in certain exact relation tothe horizontal and vertical diameter of the face of the knob, asdetermined by the name thereon, can always be found by drilling a holeat the shank to insert the pin, even if it is not so inserted when theknob is first attached. It may be more convenient in some cases, insteadof locating the hole for the pin in definite relation to the name, touse some slight index-mark upon the margin of the base of the knob forthe same purpose as indicated by the letter 0 on Figs. 2, 4:, and 5.

Of the several forms of depressions in the surface of the ten on, whichare illustrated, the non continuous form of mere countersinks (shown inFig. 5) I deem usually preferable, since that form of depression notonly prevents the knob from being withdrawn longitudinally, but alsoprevents it turning in the shank, which latter result is not invariablyobtained by circular or spiral grooves.

I claim 1. An organ-stop knob of porcelain or glass or like material,comprising the body and the tenon projecting from its base, and theshank having an end socket to receive the tenon, the

surface of the said tenon being formed with depressions a, the knob andits shank being secured together by plastic cement capable of hardening,placed in the socket and about the tenon, substantially as set forth.

2. An organ-stop knob of porcelain or glass or like material, comprisingthe body and the tenon A, having superficial depressions a, incombination with the shank having the end socket, B, the annulus ofmaterial of the shank which bounds said socket having formed on itsinner surface depressions b, said knob and shank being secured togetherby plastic cement placed in the socket and about the shank, and enteringthe depressions in both, substantially as set forth.

In testimony whereof I have set my hand, in the presence of twowitnesses, at Chicago, Illinois, this Jlth day of April, A. D. 1888.

MELVILLE CLARK.

lVitn esses:

CHAS. S. BURTON, JOHN R. NETTENs'rRoM.

